Manufacture of 2-oxy-1-aryl naphthylamines



Patented July 3, i923.

entree snares earner @FEEQ ANDRE WAHL, F ENGHIEN,

AND ROBERT LANTZ, OF PARIS, FRANCE, ASSIGNORS OF mnm- N H o 50 1mm ANONMYE DES MATIEBES COLOBANTES & PBODUITS CHIEIIQUES DE SAINT-BERKS, 0F PAP LIS, FRANCE.

WUFACTURE OE Q-OKY-l-ABYL NAPHTHYLAMINES.

Ho Drawing.

The last-named has been recently identified, forming the subject-matter of a pat ent application of Kalle & 00., published in Berlin on the 9th May 1921.

The general method for obtaining these compounds consists in the reaction of aniline on the corresponding amino-, oxyor dioxynaphthalenes. Thus, 2 :7 -dioxynaphthalene,

v heated with aniline at 190 C. for 10 hours (0. Fischer and Shiitte, Berichte, vol. 26,

page 3087, Kalle & Co., German specification 60103) or heated with aniline in pres ence of calcium chloride (Clausius, Berlchte vol. 23, page 517) furnishes 2:7-oxyphenyl-' naphthylamine in addition to the diphenyl a5 derivative. So also, 1:3-dioxynapht alcne yields under the same conditions 1-oxy-3- -henylnaphthylamine (Friedlaender and udt, Berichte vol. 29, page 1609). Finally, aniline at 180 C. transforms lze-aminoonHn-Nin in which X indicates a halogen element and so RNH a primary amine.

Primary bases have fre uently been caused to react with halo en erivatives of naphthols but the results 0 tained have been very different from those obtained by our- :5 selves. Thus Reverdin and Crepieux Application filed February M, 1922. Serial No. 586,507.

niaihthol into 1:4-oxyphenylnaphthylamine alleaforesaid patent application).

As to the 1 :Q-derivative corresponding with the following formula I, this has been obtained by reduction of the naphthoquinone-anilide (Ruler Ber. vol. 39, page 1038).

N ow we have found that it is easy to obtam oxyarylnaphthylamines corresponding with the 0xy-phenylnaphthylamine isomeric with .the preceding one and shown in formula II, by a reaction entirely different from those aforesaid. We have found, contrary to expectation that the halogen element of the oz-halogen-{i-naphthols possesses great mobility which fits it for a certain number of reactions.

This particular mobility is unexpected because the halogen derivatives of phenol whether chloroor bromo-derivatives, are remarkable as having their halogen element very firmly fixed to the nucleus (Farbenfabriken Bayer German patent specification 249,939).

It would not appear on the face of it, therefore, that the halogen element contained in the molecule of the naphthol would behave differently.

However, we have found that by causing primary amines to react with oz-chloro or c-bromo-(5-naphthol, under certain conditions there is easily obtained the substitution of an aryl group for the halogen, in accordance with the equation:

(Berichte vol. 28, page 3049) found that a red coloured derivative is formed when a-chloro-a-naphthol or its carbonate is heated with aniline. (Journal of the Chemical Society 1884, pa e 158) v obtained t-naphthoquinone-dianili e by heating dibromo-arnaphthol with aniline On the other hand, .Meldola in excess. These are very complex reactions which have nothingin common with the regular reaction that we have observed.

The action of z-halogen-{5-naphthol on a primary amine/may be carried out under very varied conditions, for instance by heat ing the reacting bodies to a suitable teniperature, it may be within a suitable solventor with addition of a subdivided metal like zinc. precipitated tin. iron, lead or copper. But in this last case, while the speed of the reaction is accelerated. formation of secondary reactions is favoured.

The following examples illustrate the iiivention. the parts being" by weights Example [.In a reflux apparatus a mixture of 1 part of a-chloro-(i-naphthol and 5 arts of aniline is boiled for about 3 or 4 ours. The progress of the reaction may be followed by observing the hydrogen chloride liberated. and when the reaction is complete the excess of aniline and of the chloronaphthol is removed. should any rc main. by a current of steam. The residual product is then washed with dilute caustic soda solution; the alkaline solution is acidi tied, the precipitate collected and purified by crystallisation first from benzene and then from a mixture of acetic and formic acids.

It forms white needles which become reddish-grey in air andcorresponds analytically with the formula C H XQ.

Per Per cent. cent NH-cai.

They are insoluble in cold water. little soluble in boilinp water. soluble in caustic alkalies, from which solutions acids reprecipitate the original product. The alkaline solution becomes colored in air and covered with a yellowish pellicle, which is a product of oxidation.

Example ll.-1 part of a-bromo-{5- naphthol and 5 parts of para-toluidine are heated together in a bath of paraflin at.

125-130- C. for 23 hours; the product thickens owing to the formationof crystals. It is treated with dilute hydrochloric acid which eliminates the excess of the base and the residual product is first distilled in steam, to expel any a-bromo-naphthol which may remain, and then purified by crystallisation from benzene or from a mixture offormic and acetic acids.

The 2-oxy-1-paratolylnaphthylamine thus obtained forms white crystals melting at 137-138 C, the chemical properties of which-are very similar to those of the product obtained by Example I.

In the foregoing examples the aniline or;

the toluidine can be exchanged for other primary bases.

Having thus described the nature of the I said invention and the best means we know of carrying the same into practical effect, we Cl 11II1Z- 1. The herein described manufacture of" Q-oxy-l-aryl-naphthylamines by causing primary amines to react .with whalogen-finaphthols. p

2. As a new manufactured product, the 2-oxy-l-aryl-naphthylamines having at the ordinary temperature the form of c stals which are insoluble in water but solu le in the caustic alkalies and 'are precipitated from their solution in the caustic alkalies by the acids.

3. The manufacture of 2-oxy-l-phenylnaphthylaniine by causing aniline to react with a halogeno {5 naphthol.

4t. Q-oxy-l-phenylnaphthylamine consisting of insoluble crystals melting at 153154 C., soluble in the caustic alkalies and precipi tated from its solution in the caustic alkalies by the acids, the alkaline solution becoming colored in air. 5

In testimony whereof we have signed this specification. ANDRE VVAHL. RQBERT LANTZ. 

